The present invention relates to an insulation-displacement connecting device for connecting two electric cables.
An insulation-displacement connecting device allows an electric cable to be connected to a conducting part without the need beforehand to strip one end of the electric cable. The insulation-displacement connecting device locally bares the cable, for example by cutting into the insulating sheath which lies around the conducting core, before making electrical contact between the conducting core thus locally bared and the conducting part.
Documents EP-0 247 360 or alternatively FR-2 723 474 disclose insulation-displacement connecting devices. An insulation-displacement connecting device comprising two insulation-displacement slots is disclosed by document FR-2 675 953. Here, the two holding and insulation-displacement slots are aligned and are intended for the connection of one self same electric wire.
The known insulation-displacement connecting devices allow an electric cable of predetermined diameter, or the predetermined diameter of which lies in a fairly restricted predetermined range of diameters, to be connected. Furthermore, when the known insulation-displacement connecting devices allow two electrical cables to be connected, these have both to be of the same diameter.
It is therefore an object of the present invention to provide an insulation-displacement connecting device that allows two cables of different diameters to be connected.
To this end, the device that the present invention proposes is an insulation-displacement connecting device for connecting at least two electric cables having a conducting core and an insulating sheath, the device comprising an insulation-displacement and retaining slot. Document EP-0 247 360 for example discloses such a device.
According to the invention, this device comprises:
at least one other insulation-displacement and retaining slot (18) known as the second such slot, essentially parallel to the first and offset with respect to the direction of the slots,
a pusher intended to accommodate two electric cables at least and shaped in such a way that each cable can lie transversely facing an insulation-displacement and retaining slot,
means of connection between the slots and the pusher allowing a relative displacement of the slots and of the pusher and guiding this displacement, and
means for bringing about the relative displacement of the pusher and of the insulation-displacement slots.
Thus, two insulation-displacement and retaining slots each allow one electric cable to be connected. The connecting of one cable is therefore not influenced by the connecting of the other cable. The connecting of two cables of different diameters may be envisioned.
In a first embodiment of a connecting device according to the invention, the two insulation-displacement and retaining slots are made in a blade bent into a U having two parallel branches of different lengths, each slot opening at the free end of each branch. The two insulation-displacement and retaining slots are therefore made in one and the same conducting part.
In this form of embodiment, the pusher comprises, for example, two profiled parts extending in the plane containing the two slots, transversely with respect to the slots, and openings are advantageously provided for the passage of each slot and of the corresponding edges through the profiled parts. In this case, the width of each opening is, for example, such that it allows the part carrying the corresponding slot to be guided and closes the edges of the slot together so that they press against the metal core of a connected cable. The material used for the blade may therefore be chosen essentially for its good conducting properties without paying too much attention to its elastic mechanical properties needed to ensure that the edges of the slot press firmly against the bared conducting metal core thereby ensuring good electrical contact.
Provision may be made for the slots to be moveable with respect to the pusher, but of course it is also possible to have a pusher which can move and slots which are fixed. Another solution which is more complicated to implement would be to have slots and a pusher all of which could move.
When the slots can move, a screw is, for example, provided for displacing the slots, this screw being engaged in a metal part connecting the two slots and incapable of translational movement with respect to an insulating casing.
The relative movement of the slots and the pusher is, for example, a translational movement or alternatively a pivoting movement.
When the relative movement of the slots and the pusher is a pivoting movement, provision may be made for the slots to be carried by parallel curved blades, for the pusher to be mounted so that it can pivot and to have two housings essentially transversal with respect to the slots, openings being provided for the passage of the blades carrying the slots.
A screwdriver blade may be intended to perform the pivoting movement of the pusher. A housing intended to accommodate the end of such a blade is then advantageously provided in the pusher.
The present invention also relates to a junction unit in which a connecting device as described hereinabove is placed.